lock INFINITI QX56 2006 Factory User Guide

PRECAUTIONSAT-9
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Revision: November 2009 2006 QX56
Service Notice or PrecautionsECS00CDM
ATF COOLER SERVICE
If A/T fluid contains frictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T fluid cooler mounted in the radiator or replace the radiator. Flush cooler lines using
cleaning solvent and compressed air after repair. For A/T fluid cooler cleaning procedure, refer to AT- 1 4 , "
A/T
Fluid Cooler Cleaning" . For radiator replacement, refer to CO-14, "RADIATOR" .
CHECKING AND CHANGING A/T FLUID SERVICE
Increase ATF temperature by 80°C (176 °F) once, and then check ATF level in 65° C (149°F) when adjusting
ATF level.
NOTE:
JA60 uses both systems of a water-cooling and of an air-cooling. Air-cooling system has a by-pass valve.
When ATF temperature is not over 50 °C (122 °F) with water-cooling system OFF, it does not flow to air-cooling
system. If ATF level is set without the flow of ATF, the level will be 10mm lower than the standard. Therefore,
piping should be filled with ATF when adjusting level.
OBD-II SELF-DIAGNOSIS

A/T self-diagnosis is performed by the TCM in combination with the ECM. Refer to the table on AT- 8 6 ,
"SELF-DIAGNOSTIC RESULT MODE" for the indicator used to display each self-diagnostic result.

The self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM mem-
ories.
Always perform the procedure on AT- 3 9 , "
HOW TO ERASE DTC" to complete the repair and avoid
unnecessary blinking of the MIL.
For details of OBD-II, refer to EC-48, "
ON BOARD DIAGNOSTIC (OBD) SYSTEM" .

Certain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .

PREPARATIONAT-11
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Revision: November 2009 2006 QX56
Commercial Service ToolsECS00ENT
ST25850000
(J-25721-A)
Sliding hammerRemove oil pump assembly
a: 179 mm (7.05 in)
b: 70 mm (2.76 in)
c: 40 mm (1.57 in)
d: M12X1.75P
—
(J-47002)
Transmission jack adapter kit
1. —
(J-47002-2)
Center bracket
2. —
(J-47002-3)
Adapter plate
3. —
(J-47002-4)
Adapter block Assist in removal of transmission and transfer
case as one assembly using only one trans-
mission jack.
Tool number
(Kent-Moore No.)
Tool name
Description
NT422
WCIA0499E
Tool name
Description
Power tool Loosening bolts and nuts
Drift Installing manual shaft seals
a: 22 mm (0.87 in) dia.
Drift Installing rear oil seal (4WD models)
a: 64 mm (2.52 in) dia.
PBIC0190E
NT083
SCIA5338E

AT-14
A/T FLUID
Revision: November 20092006 QX56

To check the ATF level, insert the ATF level gauge until
the cap contacts the top of the charging pipe, with the
gauge reversed from the normal inserted position as
shown.
8. Check the ATF condition.

If the ATF is very dark or has some burned smell, there may be an internal problem with the transmis-
sion. Refer to AT- 1 7 6 , "
TROUBLE DIAGNOSIS FOR SYMPTOMS" . Flush the transmission cooling
system after repairing the transmission.

If the ATF contains frictional material (clutches, bands, etc.), replace the radiator and flush the transmis-
sion cooler lines using cleaning solvent and compressed air after repairing the transmission.
9. Install the ATF level gauge in the ATF charging pipe and install the level gauge bolt.
10. Tighten the level gauge bolt to specification.
A/T Fluid Cooler CleaningECS00CDS
Whenever an automatic transmission is repaired, overhauled, or replaced, the A/T fluid cooler mounted in the
radiator must be inspected and cleaned.
Metal debris and friction material, if present, can become trapped in the A/T fluid cooler. This debris can con-
taminate the newly serviced A/T or, in severe cases, can block or restrict the flow of A/T fluid. In either case,
malfunction of the newly serviced A/T may result.
Debris, if present, may build up as A/T fluid enters the cooler inlet. It will be necessary to back flush the cooler
through the cooler outlet in order to flush out any built up debris.
A/T FLUID COOLER CLEANING PROCEDURE
1. Position an oil pan under the automatic transmission's inlet and outlet cooler hoses.
2. Identify the inlet and outlet fluid cooler hoses.
3. Disconnect the fluid cooler inlet and outlet rubber hoses from the steel cooler tubes or bypass valve.
NOTE:
Replace the cooler hoses if rubber material from the hose
remains on the tube fitting.
4. Allow any A/T fluid that remains in the cooler hoses to drain into the oil pan.
5. Insert the extension adapter hose of a can of Transmission Cooler Cleaner (Nissan P/N 999MP-AM006) into the cooler out-
let hose.
CAUTION:

Wear safety glasses and rubber gloves when spraying
the Transmission Cooler Cleaner.

Spray cooler cleaner only with adequate ventilation.

Avoid contact with eyes and skin.

Do not breath vapors or spray mist.
SCIA1684E
Level gauge bolt: : Refer to AT- 2 5 0 , "Components" .
SCIA3830E
SCIA3831E

AT-20
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
CLUTCH AND BAND CHART

—Operates

—Operates during “progressive ” acceleration.

—Operates and effects power transmission while coasting.

—Line pressure is applied but does not affect power transmission.

—Operates under conditions shown in HLR/C Operating Condition

— Operates under conditions shown in LC/B Operating Condition. Delay control is applied during D (4,3,2,1)
N shift.
Shift position I/C HLR/C D/C R/B FR/B LC/B Fwd/B
1st
OWC Fwd
OWC 3rd
OWC Remarks
P PARK POSITION
R REVERSE
POSITION
N NEUTRAL POSI-
TION
D 1st
Automatic shift
1 ⇔ 2⇔ 3⇔ 4⇔ 5
2nd
3rd4th
5th
1st
4 2nd
Automatic shift
3rd 1
⇔ 2⇔ 3⇔ 4
4th
3 1st
Automatic shift1⇔ 2⇔ 3⇐ 4
2nd
3rd 4th
2 1st
Automatic shift1⇔ 2⇐ 3⇐ 4
2nd
3rd4th
1 1st
Locks (held sta-tionary in 1st
gear)
1 ⇐ 2⇐ 3⇐ 4
2nd
3rd
4th

AT-30
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
TCM FunctionECS00CDW
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, lock-up operation, and engine brake operation.

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)

TCM

ACTUATORS
PNP switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Stop lamp switch signal
Turbine revolution sensor
1st position switch signal
4th position switch signal
ATF pressure switch signal
Tow mode switch signal Shift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN system
Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Starter relay
Back-up lamp relay
SCIA5624E

A/T CONTROL SYSTEMAT-31
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CAN CommunicationECS00CDX
SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-26,
"CAN COMMUNICATION" .
Input/Output Signal of TCMECS00CDY
*1: Spare for vehicle speed sensor·A/T (revolution sensor)
*2: Spare for accelerator pedal position signal
*3: If these input and output signals are different, the TCM triggers the fail-safe function.
*4: CAN communications Control item
Line
pressure
control Vehicle
speed
control Shift
control Lock-up
control Engine
brake
control Fail-safe
function
(*3) Self-diag-
nostics
function
Input Accelerator pedal position signal
(*4)XXXXXXX
Vehicle speed sensor A/T
(revolution sensor) XXXX
XX
Vehicle speed sensor MTR
(*1) (*4)XXXX X
Closed throttle position signal
(*4)(*2) X (*2) X X (*2) XX
Wide open throttle position signal
(*4)(*2) X (*2) X (*2) XX
Turbine revolution sensor 1 XX X XX
Turbine revolution sensor 2
(for 4th speed only) XX
XXX
Engine speed signals
(*4)XX
PNP s witch XXXXXXX
A/T fluid temp eratu re senso rs 1, 2XXXXXXX
ASCD Operation signal
(*4)XXXX
Overdrive cancel
signal
(*4)XX X
TCM power supply voltage signal XXXXX X
Out-
put Direct clutch solenoid (ATF pres-
sure switch 5)
XX
XX
Input clutch solenoid (ATF pressure
switch 3) XX
XX
High and low reverse clutch sole-
noid (ATF pressure switch 6) XX
XX
Front brake solenoid (ATF pressure
switch 1) XX
XX
Low coast brake solenoid (ATF
pressure switch 2) XX
XXX
L in e p re ssu re s olen oid XXXXXXX
TCC solenoid XX X
Sta rter rela y XX

AT-34
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
Shift Change System Diagram
*1: Full phase real-time feedback control monitors movement of gear ratio at gear change, and controls oil
pressure at real-time to achieve the best gear ratio.
Lock-up ControlECS00CE1
The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.
The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid valve,
which is controlled by a signal from TCM, and the torque converter clutch control valve engages or releases
the torque converter clutch piston.
Lock-up Operation Condition Table
TORQUE CONVERTER CLUTCH CONTROL VALVE CONTROL
Lock-up Control System Diagram
Lock-up Released

In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.
PCIA0013E
Select leverD position4 position 3 position 2 position
G ea r p osit io n 54432
Lock-up ×–×××
Slip lock-up ××–––
PCIA0014E

A/T CONTROL SYSTEMAT-35
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Lock-up Applied

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the
torque converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
SMOOTH LOCK-UP CONTROL
When shifting from the lock-up released state to the lock-up applied state, the current output to the torque con-
verter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.
Half-clutched State

The current output from the TCM to the torque converter clutch solenoid is varied to gradually increase
the torque converter clutch solenoid pressure.
In this way, the lock-up apply pressure gradually rises and while the torque converter clutch piston is put
into half-clutched status, the torque converter clutch piston operating pressure is increased and the cou-
pling is completed smoothly.
Slip Lock-up Control

In the slip region, the torque converter clutch solenoid current is controlled with the TCM to put it into the
half-clutched state. This absorbs the engine torque fluctuation and lock-up operates from low speed.
This raises the fuel efficiency for 4th and 5th gears at both low speed and when the accelerator has a low
degree of opening.

AT-36
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
Engine Brake ControlECS00CE2

The forward one-way clutch transmits the drive force from the engine to the rear wheels. But the reverse
drive from the rear wheels is not transmitted to the engine because the one-way clutch is idling.
Therefore, the low coast brake solenoid is operated to prevent the forward one-way clutch from idling and
the engine brake is operated in the same manner as conventionally.

The operation of the low coast brake solenoid switches the low coast brake switching valve and controls
the coupling and releasing of the low coast brake.
The low coast brake reducing valve controls the low coast brake coupling force.
Control ValveECS00CE3
FUNCTION OF CONTROL VALVE
SCIA1520E
NameFunction
Torque converter regulator valve In order to prevent the pressure supplied to the torque converter from being excessive,
the line pressure is adjusted to the optimum pressure (torque converter operating pres-
sure).
Pressure regulator valve
Pressure regulator plug
Pressure regulator sleeve Adjusts the oil discharged from the oil pump to the optimum pressure (line pressure) for
the driving state.
Front brake control valve When the front brake is coupled, adjusts the line pressure to the optimum pressure
(front brake pressure) and supplies it to the front brake. (In 1st, 2nd, 3rd, and 5th gears,
adjusts the clutch pressure.)
Accumulator control valve Adjusts the pressure (accumulator control pressure) acting on the accumulator piston
and low coast reducing valve to the pressure appropriate to the driving state.
Pilot valve A Adjusts the line pressure and produces the constant pressure (pilot pressure) required
for line pressure control, shift change control, and lock-up control.
Pilot valve B Adjusts the line pressure and produces the constant pressure (pilot pressure) required
for shift change control.
Low coast brake switching valve During engine braking, supplies the line pressure to the low coast brake reducing valve.
Low coast brake reducing valve When the low coast brake is coupled, adjusts the line pressure to the optimum pressure
(low coast brake pressure) and supplies it to the low coast brake.
N-R accumulator Produces the stabilizing pressure for when N-R is selected.
Direct clutch piston switching valve Operates in 4th gear and switches the direct clutch coupling capacity.
High and low reverse clutch control valve When the high and low reverse clutch is coupled, adjusts the line pressure to the opti-
mum pressure (high and low reverse clutch pressure) and supplies it to the high and low
reverse clutch. (In 1st, 3rd, 4th and 5th gears, adjusts the clutch pressure.)

A/T CONTROL SYSTEMAT-37
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FUNCTION OF PRESSURE SWITCH
Input clutch control valveWhen the input clutch is coupled, adjusts the line pressure to the optimum pressure
(input clutch pressure) and supplies it to the input clutch. (In 4th and 5th gears, adjusts
the clutch pressure.)
Direct clutch control valve When the direct clutch is coupled, adjusts the line pressure to the optimum pressure
(direct clutch pressure) and supplies it to the direct clutch. (In 2nd, 3rd, and 4th gears,
adjusts the clutch pressure.)
TCC control valve
TCC control plug
TCC control sleeve Switches the lock-up to operating or released. Also, by performing the lock-up operation
transiently, lock-up smoothly.
Torque converter lubrication valve Operates during lock-up to switch the torque converter, cooling, and lubrication system
oil path.
Cool bypass valve Allows excess oil to bypass cooler circuit without being fed into it.
Line pressure relief valve Discharges excess oil from line pressure circuit.
N-D accumulator Produces the stabilizing pressure for when N-D is selected.
Manual valve Sends line pressure to each circuit according to the select position. The circuits to which
the line pressure is not sent drain.
Name
Function
NameFunction
Pressure switch 1 (FR/B) Detects any malfunction in the front brake hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 2 (LC/B) Detects any malfunction in the low coast brake hydraulic pressure. When it detects any
malfunction, it puts the system into fail-safe mode.
Pressure switch 3 (I/C) Detects any malfunction in the input clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 5 (D/C) Detects any malfunction in the direct clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 6 (HLR/C) Detects any malfunction in the high and low reverse clutch hydraulic pressure. When it
detects any malfunction, it puts the system into fail-safe mode.